This invention relates to linear motors in general, and more particularly, to a linear motor for propelling track bound vehicles.
A linear motor having a stator disposed on a track, which stator is provided with devices for its retention on the railbed and which has conductors of a traveling wave winding imbedded in a non-magnetic winding support, is disclosed in U.S. Pat. No. 3,924,537. As described therein, two exciter windings having horizontal coil axes are disposed on a vehicle. A traveling wave winding consisting of electrical conductors of rectangular cross section is disposed on the railbeds and cooperates with the exciter windings on the vehicle. The space between and around the electrical conductors on the roadbed is filled with an electrical insulator of epoxy resin, polyester resin or the like in such a way that a rail is formed. The conductors are brought out at the two ends of the rail permitting rails which are lined up to be connected together. The rails, after being lined up, are secured to the roadbed in an up-ended manner utilizing an intermediate support and protrude between the two windings of the exciter magnet which is disposed on the vehicle. A particular disadvantage of this design is that track elements which are cantilevered are employed. These cause difficulties particularly at track crossings and junctions.
A simple construction of the railbed and of switches can be achieved by using a single-sided linear motor which has an exciter winding disposed on the vehicle with the vertical coil axis, along with the multi-phase traveling wave winding arranged flat on the railbed for the drive of the vehicle. Such is disclosed in the publication, "Research and Development on Electrodynamic Levitation in West Germany" AEG-BBC-Siemens, Catalog No. E 41 PM/1393, page 15. In such a design, the line is divided into individual feed sections and possesses a star-connected three-phase current winding fed by a static frequency changer subunit. A superconducting exciter winding on the vehicle cooperates with the three-phase winding accomodated in the track.